Delivery charged not updating on checkout page after update

I updated my woocommerce plugin a few days ago and now my delivery charges as determined by the shipping class assigned to the product.
So for example here are my shipping classes:
https://www.dropbox.com/s/4lglqon23h1bzy1/shipping%20class.PNG?dl=0

now when you add a product and go to checkout it just shows “delivery charge”
https://www.dropbox.com/s/uq9u4lchdywov3m/delivery%20charge%20error.PNG?dl=0

before the update it used to show the exact delivery charge as per shipping class of the product e.g. it would say “delivery charges Rs. 150” or delivery charges rs. 300

now if I go to an item that is Free delivery, it still shows delivery charge
https://www.dropbox.com/s/9napc3yp69esssn/free%20delivery%20error.PNG?dl=0

please help!